This invention relates to a color cathode ray tube comprising an in-line electron gun having at least one electrode which includes a substantially flat grid with apertures for allowing passage of electron beams, and a tubular part which is connected to said flat grid.
Such color cathode ray tubes are known and are used, inter alia, in display devices such as color television receivers and color monitors for computers.
When such color cathode ray tubes are in operation, three electron beams are generated by an in-line electron gun. Said electron beams are accelerated and focused by means of electrodes. Some of the electrodes, particularly those which are at a relatively high voltage, are provided with more or less tubular parts which extend substantially parallel to the electron beams. One of the functions of these tubular parts is to shield the electron beams from external electric and/or magnetic fields. For the known color cathode ray tubes, these parts are made by means of a deep drawing process, in which said part and the flat grid are made in a single piece, or said part consists of a piece of deep-drawn tube to which the flat grid has been welded.
However, ever higher demands are imposed on the accuracy with which the various parts of an electron gun are manufactured. Moreover, in the case of color cathode ray tubes, the high-voltage sensitivity is a constantly recurring problem.